Silicic acid mixtures and use thereof as insulation material

Abstract

Highly efficient thermal insulation is produced at low cost by blending pyrogenic silica with a silicon-containing ash, the mixture thus produced containing no perlite. The pyrogenic silica has a synergistic effect in lowering thermal conductivity.

1 .- 12 . (canceled) 
     
     
         13 . A mixture comprising pyrogenic silica and more than 50% by weight of at least one silicon-containing ash, wherein the mixture is free of perlite. 
     
     
         14 . The mixture of  claim 13 , wherein the mixture comprises more than 60% by weight of silicon-containing ash. 
     
     
         15 . The mixture of  claim 13 , wherein the silicon-containing ash consists of rice hull ash. 
     
     
         16 . The mixture of  claim 14 , wherein the silicon-containing ash consists of rice hull ash. 
     
     
         17 . The mixture of  claim 13 , wherein the silicon-containing ash contains silica fume. 
     
     
         18 . The mixture of  claim 14 , wherein the silicon-containing ash contains silica fume. 
     
     
         19 . The mixture of  claim 15 , wherein the silicon-containing ash contains silica fume. 
     
     
         20 . The mixture of  claim 13 , wherein the silicon-containing ash consists of rice hull ash and silica fume. 
     
     
         21 . The mixture of  claim 14 , wherein the silicon-containing ash consists of rice hull ash and silica fume. 
     
     
         22 . The mixture of  claim 13 , wherein at least one IR opacifier is present. 
     
     
         23 . The mixture of  claim 14 , wherein at least one IR opacifier is present. 
     
     
         24 . The mixture of  claim 15 , wherein at least one IR opacifier is present. 
     
     
         25 . The mixture of  claim 19 , wherein at least one IR opacifier is present. 
     
     
         26 . The mixture of  claim 13 , wherein at least one fiber material is present. 
     
     
         27 . The mixture of  claim 26 , wherein at least one fiber material comprises cellulosic fibers. 
     
     
         28 . A process for producing thermal insulation material, comprising producing a mixture of  claim 13  and introducing this mixture into an envelope, with no sintering occurring in the process and the insulation material not containing any perlite. 
     
     
         29 . The process of  claim 28 , wherein the insulation material is processed to produce a shaped body. 
     
     
         30 . The process of  claim 29 , wherein the shaped body is an insulation mat, an insulation board or a vacuum insulation panel. 
     
     
         31 . A thermal insulation material, comprising a mixture of  claim 13 . 
     
     
         32 . A building insulation material comprising a mixture of  claim 13 .